This invention relates to a method and appatus for controlling an accumulating wheel which is used for accumulating bills in an automatic depositing and dispensing machine or the like, and more particularly to a method and apparatus for preventing collision between a bill and blades of the accumulating wheel.
An accumulating wheel has a function of accumulating and arranging bills in a storage section after receiving between a plurality of blades each bill intermittently sent from a conveying mechanism comprising a belt conveyor or the like. A large number of such accumulating wheels are used in bank machines for handling bank notes, such as in automatic teller machines, etc. In a conventional accumulating wheel, in order to positively feed a bill in between the blades and prevent collision between the bill and blades, the rotation of the blades is controlled, for instance, by a method as disclosed in Japanese Patent Public Disclosure No. 65757/1981.
FIG. 10 is a diagram showing the relationship between the position of a bill and the rotating angle of the accumulating wheel in a case where the aforementioned controlling method is employed. In other words, assuming that a bill enters between the blades of the accumulating wheel at a time (point * in FIG. 10), after a lapse of a fixed time Tx from a time (point x in FIG. 10) at which the bill has passed a specific position in the conveying passage in the machine, the rotating angles of the accumulating wheel at the time when a sensor detects the bill passing the specific position in the conveying passage are classified into the following: safe timings Ts.sub.1, Ts.sub.2, Ts.sub.3, . . . at which the advancing direction of a bill does not intersect a blade of the accumulating wheel at the time (point .circleincircle. in FIG. 10) when the bill is expected to enter the rotating range of the accumulating wheel; risky timings Td.sub.1, Td.sub.2, . . . before and after intersecting timings Tc.sub.1, Tc.sub.2, . . . at which the advancing direction of the bill intersects the tip of a blade of the accumulating wheel; and intermediate timings Tn.sub.1, Tn.sub.2, Tn.sub.3, Tn.sub.4, . . . which cannot be judged to fall under either of the two categories just mentioned.
In a case where the point x in FIG. 10 falls under the category of dangerous timings (the two cases of 1 and 2 in FIG. 10), the timing (the point .circleincircle. in FIG. 10) of entry of a bill is shifted to the next safe timing Ts.sub.3 by speeding up the rotating speed of the accumulating wheel over a fixed time Ty (the time from the poing * up to the point .circle. ). In other words, according to this controlling method, a dangerous timing is prevented by increasing the speed of the accumulating wheel above its normal rotation speed (a low speed) over a fixed time.
However, the aforementioned controlling method is an extremely simple one in that the wheel is rotated at a high speed uniformly over Ty on condition that the point x is present in the dangerous timings Td.sub.1, Td.sub.2, . . . . Therefore, it cannot be said that no collision will occur between the bill and the blade in cases where the point x falls, for instance, within the intermediate timings Tn.sub.1, Tn.sub.2, . . . .